The invention relates to an arrangement for adjusting the positions of the hands of a timepiece, especially a wristwatch, which includes a hand position setting shaft carrying for rotation therwith a coupling drive and a coupling drive lever in engagement with the coupling drive.
A watch including such a hand position adjustment mechanism is well-known in the prior art.
In such hand position adjusting arrangements the position setting control shaft is generally coupled with the hand drive mechanism by outward pulling of the control shaft. Pressing the control shaft back into the housing causes again disengagement of the control shaft from the hand drive mechanism. Such arrangements have proved to be not only reliable but all watch owners are familiar with such mechanisms and like them.
In present watch adjustment mechanisms a coupling operation member is mounted on the control shaft for rotation therewith and is provided with a circumferential groove into which a portion of a coupling operating lever projects directly or into which a pin mounted on the coupling operating lever projects for operation of the lever by axial movement of the control shaft. Such a design is generally quite sturdy and can withstand the sometimes rough handling thereof by the user of a watch. It requires however a relatively large amount of space since the coupling operating member surrounds the control shaft and is provided with such a groove so that the operating member needs to have a relatively large diameter to provide sufficient material at the bottom of the groove for the square passage within. If, on the other hand, the groove is formed at the end of the adjustment shaft where it could be formed in a section without passage if the passage were formed as a blind hole, then the shaft and coupling operating member become relatively long. It is also noted that the manufacture of such small parts with blind holes for mounting the part on the control shaft is extremely difficult particularly since the cross-sectional area of the blind hole needs to be out of round.
In the process of miniaturizing the water mechanisms it is becoming quite difficult to accommodate the present adjustment structures, so much that, in some cases, the given mechanisms have been omitted and replaced by separate adjustment buttons which however have encountered opposition by the watch buyers.
It is therefore the principal object of the present invention to provide a watch adjustment mechanism of the type described which is as sturdy and as easy to manufacture as the prior art arrangements but which, in contrast, occupies substantially less space.